From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fieldses.org ([174.143.236.118]:43219 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754744Ab0JNOLn (ORCPT ); Thu, 14 Oct 2010 10:11:43 -0400 Date: Thu, 14 Oct 2010 10:11:42 -0400 To: DENIEL Philippe Cc: linux-nfs@vger.kernel.org Subject: Re: Effect of NFS4ERR_DELAY on the client Message-ID: <20101014141142.GD24146@fieldses.org> References: <4CB6EE0D.5060303@cea.fr> Content-Type: text/plain; charset=us-ascii In-Reply-To: <4CB6EE0D.5060303@cea.fr> From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Thu, Oct 14, 2010 at 01:48:29PM +0200, DENIEL Philippe wrote: > Hi, > > I have a question about NFS4ERR_DELAY. What is the behavior of the > client when such an error is returned. Does it retry ? If yes, how > many times and with what kind of interval between each retry ? > Is the behavior similar to what the NFSv3 client when receiving > NFS3ERR_JUKEBOX ? > My purpose is to run NFSv4.x on top of a namespace whose entries can > be migrated : opening a file may require staging it (in this case > NFS4ERR_DELAY and NFS3ERR_JUKEBOX will be returned) For the linux client, see fs/nfs/nfs4proc.c:nfs4_delay() and nfs4_handle_exception(): looks like it starts with NFS4_POLL_RETRY_MIN == .1 second, and doubles it each time up to NFS4_POLL_RETRY_MAX == 15 seconds. --b.